Ah, the old wedding film problem: dark blacks and bright whites! Moire problems are better avoided (checks, stripes etc). If you have complete control (ie not a wedding) then costuming is probably more determined by character and setting than anything else.

I just took some stills a barbecue pitmaster wearing a bright white butcher's apron in front of his smoker with sunlight coming in. The smoker is black metal, very hard to capture the full dynamic range of colors.

You should watch television newscasts for ideas on color. If you have control, just run a test and shoot the talent wearing the clothing, that should tell you if you are going to run into issues. If you have full control like for a movie, the costumes should be part of the overall production design.

Another issue is not to have your talent blend into your background. This happened on Pres. Bush's speech from New Orleans the other night, they lit the background with pale blue lights and Bush wore a light blue shirt. It almost looked like his head was floating in space.